Instrument for platting surveys



W- J- CARD. Machine for Plotting Surveys, &c. 7

N0. 2;561. I r Patented April 16, 1842.

N. vzrzna Phnlo-Ulhngnpher. Wamington, u. a

TAT

N r se WM. .I. CARD, OF LANCASTER, OHIO.

INSTRUMENT FOR PLATTING- SURVEYS.

To all whom it may concern:

Be it known that I, WILLIAM J. CARD, of Lancaster, in the county ofFairfield and State of Ohio, have invented a new and useful Machine forPlatting all Kinds of Surveys; and I do hereby declare that thefollowing is a full and exact description.

The nature of my invention consists in providing four pieces of wood ormetal graduated in any of the known ways of graduating protractors orsurveyors com pass, which all work on a pinion screw E as a center, withtwo clamp screws F and G to clamp the outside pieces to the center bladeB at any angle desired from 0 to 90.

To enable others skilled in the art to make and use my invention, I willproceed to describe its construction and operation.

It consists of four pieces of wood or metal, viz: the sector G, thebottom piece or semicircle A, the blade B, the nonius or top piece D.The piece marked 0 is graduated as ajsector on the edgefrom 0 right andleft int-o 60 divisions of 31 minutes each to coincide with thegraduations of the seinicircle A, and is also graduated on the top from0 right and left, into 30 divisionsof 30 minutes each. The bottom pieceor semicircle A is graduated from 0 right and left into 90. The toppiece or nonius D is graduated from 0 right and left into 30 divisionsof 31 minutes each, to coincide with the graduations on the top of thesector C. On the blade B, is laid off a diagonal scale of equal parts.All of these four pieces A, B, I), C, work on the pinion crew E as acenter. The stems of the two clamp screws F and G are made fast to theblade B. When the 0 on the nonius D, the sector C, the semicircle A,coincide, the blade B forms a right angle with the straight edge of thesemicircle A.

To plat a survey, I fasten my paper to a drawing board or table squaredfor the purpose, then loose the clamp screw G and set the semicircle Ato the desired angle; then apply the straight edge of the semicircle Ato one edge of the drawing board or table and slide it along until oneedge of the blade B coincides with the fixed point on the paper, thenwith a pen or pencil mark the direction of the course along the edge ofthe blade B to any desired length and in like manner describe any courseor angle desired from 0 to 90 right or left.

To plat an eastern or western variation, loose the clamp screw F, thenmove the sector C, to the right or left between the blade B and thenonius D the distance of the variation, then clamp the screw F andproceed as before described in platting a survey.

By this machine any kind of surveys can be platted much more accuratelyand rapidly than can be done by any method now in use.

By referring to the accompanying drawings it will be seen that I have aprotractor, right angle triangle parallel ruler, nonius or vernier, anda diagonal scale of equal parts all combined on one instrument.

What I claim as my invention and desire to secure by Letters Patentunder the name of the theolodian protractor, is

The application of a graduated circle and nonius or Vernier to a movabletriangle or right angle, combining for that purpose as above describedfour pieces of Wood or metal, namely, a semicircle, a sector, a nonius,and diagonal scale of equalparts, which latter also forms a parallelruler.

W. J. CARD.

Witnesses H. C. WHITMAN, WV. VAN HAMM.

